The evolution of non-metric dental variation in Europe

The potential for dental morphology to answer questions about human evolution in the Middle to Late Pleistocene has only recently begun to be appreciated. Non-metric dental traits provide useful information for taxonomic diagnosis as well as for assessing biological relationships among living and ancient populations. This study uses dental morphology to assess temporal change in Europe. Homo erectus serves as the presumptive primitive condition for later humans and change over time is assessed by calculating estimates of divergence between groups based on the mean measure of divergence multivariate statistic. The samples include Homo erectus (n = 12), early modern humans from Africa and West Asia (n = 12), early Neandertals (n = 16), late Neandertals (n = 20), Upper Paleolithic Europeans (n = 28) and contemporary Europeans (n = 47). The results show a marked disruption in continuity from early modern to later modern humans when Neandertals are incorporated into the temporal sequence. If Neandertals are left out of the sequence the change in divergence values conforms to expectations for gradual evolution toward the modern human condition (e.g., distance values get progressively smaller through time). At minimum this should set to rest any idea that modern Europeans evolved directly from Neandertal ancestors. Late Neandertals are somewhat less ‘specialized’ than early Neandertals; the implications of this finding are discussed.

A close up of Neanderthal teeth from Krapina, showing a high degree of shovelling. According to an observation by Coon, the teeth of the Grimaldi boy were quite similar to the teeth from Krapina in some respects.

One previous study of teeth concluded…

Crummett (1994) examined the first of these two hypotheses by investigating temporal change in incisor morphology. Her results found no morphological trajectory from the Neandertal to the modern condition in Western Europe (with the caveat that data for Upper Paleolithic samples were unavailable). However, she felt that a better case for gradual evolution could be made for Central Europe. This is because she observed a trajectory of change from the incisor form observed in Neandertals to that observed in Upper Paleolithic (Dolní Věstonice) and recent Central Europeans.

A chart of the frequency of dental traits in Neanderthals. There’s more detailed information on the pdf

And another showing the mean distances between sampled groups..

Although the conclusion of this publication was that there was no evidence of significant interbreeding (which is probably correct) it doesn’t make a comment on lowlevels of interbreeding. This is probably because the low (5% or less) level suggested by a couple of DNA studies wouldn’t make a noticeable impact on the appearance of the UP European samples.